Infantile hemangiomas are made up of blood vessels that form incorrectly and multiply more than they should. These blood vessels receive signals to grow rapidly early in a baby’s life. Most infantile hemangioma will appear at birth or within the first few weeks after birth. Most infantile hemangiomas show some mark or colored patch on the skin at birth or within a few weeks after birth.
In most cases, they stop growing and begin to shrink by the baby’s first birthday. It will begin to flatten and appear less red. This phase, called involution, continues from late infancy to early childhood.